1. Field of the Invention
The present invention relates to a three-phase magneto armature having delta connection windings and, more particularly, to the construction of an armature of such a three-phase magneto.
2. Description of the Related Art
FIGS. 1 is a plan view of an armature of a known delta-connection three-phase magneto, while FIG. 2 is a connection diagram showing the connection of windings on the stator. The armature which is constructed as a stator has a core 1 which is composed of a core body 10 and a plurality of magnetic poles 11 provided on the outer periphery of the core body 10. A coil or winding 2 is wound on each magnetic pole 11 in the illustrated direction. There are six windings for each of three phases A,B and C. More specifically, the phase A includes six windings A1 to A6 which are connected in series so as to form a series winding circuit 20a. Similarly, the phases B and C respectively have six windings B1 to B6 and C1 to C6 which are respectively connected in series so as to form series winding circuits 20b and 20c, respectively. A starting end Als of the winding Al is connected to a terminal end C6e of the winding C6 through a connection conductor Xl (FIG. 2). Similarly, a starting end Bls of the winding B1 and a terminal end A6e of the winding A6, and a starting end Cls of the winding Cl a terminal end B6e of the winding B6, are respectively connected through connection conductors Y1 and Z1 (FIG. 2). Output terminals X, Y and Z are led from the respective connection conductors X1, Y1 and Z1.
The magneto further has a ring-shaped magnet surrounding the magnetic poles 11 and adapted to be rotatingly driven by, for example, an internal combustion engine. The magnet, however, is omitted from the drawings for the purpose of clarification of the illustration of critical portion of the invention.
In operation, as the magnet (not shown) rotates, a voltage is induced in each winding 2 so that a three-phase AC voltage is output from the output terminals X, Y and Z and is supplied to a load (not shown).
In the conventional three-phase magneto having the described construction, the windings 2 on all the magnetic poles 11 are wound in the same direction. Therefore, as is clear from FIG. 1, the distance between the starting end Bls of the winding B1 and the terminal end A6e of the winding A6, as well as the distance between the starting end Cls of the winding Cl and the terminal end B6e of the winding B6, is spaced by a large physical distance from each other, although the starting end Als of the winding Al is positioned close to the terminal end C6e of the winding C6. In consequence, long conductors Y1 and Z1 are required for the connection between these ends of the winding, with the results that difficulty is encountered in finding space for such conductors, as well as in providing good electrical insulation.